The Biostatistics Core will support the clinical and laboratory-based projects of this grant so that research studies are efficiently designed, conducted, monitored and analyzed. Activities will include formalization of hypotheses to be tested to ensure that valid conclusions can be Dr. awn, design of clinical trials and laboratory studies, database development, data management, and data analysis. The Biostatistics Core will provide input into the statistical aspects of the projects, including experimental design and development and validation of novel measurements, and will provide innovative and modem statistical analysis of the data. The objective is to provide statistical support as required by the projects and cores to achieve their specific aims. The statistical components of all clinical and laboratory protocols will include determination of the type of design to be used, calculation of number of experimental units (animals or patients) needed, assessment of the types of data to be collected for each study, specification of design parameters such as sample size, type I and type II error rates of tests of hypotheses, and provision for interim analyses when appropriate.